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Episode 2: How to Turn Lead into Gold

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Atoms are made of protons, neutrons, and electrons, with the protons and neutrons in the nucleus and the electrons in orbitals, as shown in the diagram below:  " Atom Diagram " by  AG Caesar  is licensed under  CC BY-SA 4.0 . This sort of diagram is quite common, but is actually somewhat misleading. For one thing, the electrons don't orbit the nucleus like a planet orbiting the star. Instead, they form sort of a cloud around the nucleus that we call "orbitals," but these are not the same as a simple orbit. Additionally, the diagram above shows the electrons being rather close to the nucleus, when this is not the case at all. They are extremely far. The following diagram is somewhat more accurate: " Helium atom QM " by  User:Yzmo  is licensed under  CC BY-SA 3.0 . The above is a helium atom. The tiny dot in the middle is the nucleus. The black cloud surrounding that dot is the space occupied by helium's two electrons. Their distance from the nucleus...
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Episode 1: Cracking the Genetic Code

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The genetic code tells us how the information in DNA is used to make proteins. But before we get there, let's break it down. DNA is a type of molecule- a nucleic acid. It is made of a whole bunch of smaller molecules called nucleotides. One nucleotide is linked to another, which is linked to another, and another, and so on. A typical DNA strand in a cell consists of millions of linked nucleotides. Each nucleotide is made of a sugar. In the case of DNA, the sugar is deoxyribose. That's where DNA gets its name: DeoxyriboNucleic Acid. Deoxyribose is a 5-carbon molecule, with each carbon bonded to one oxygen atom EXCEPT for one carbon, which we call the 2' carbon. That's what makes it "deoxy." It's missing one oxygen compared to normal ribose. The sugar is connected to at least one phosphate group (PO 4 ) on one end, and a nitrogenous base (A, T, C, or G) on the other end. Below is a typical depiction of double-stranded DNA, as well as a zoomed-in portion show...
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